Non-contact seals are known in the art and generally fall into categories of labyrinth, hybrid labyrinth, and centrifugal pressure seals. Such seals are used to keep lubricating fluids in a rotatable shaft bearing, and may also keep foreign contaminants out of the bearing.
An example of a centrifugal pressure seal for roller or ball bearings having a lubricating fluid is found in U.S. Pat. No. 6,170,832 to Ernst. In such a seal a centrifugal pumping chamber pressurizes a portion of the lubricating fluid when the bearing is rotated, and feeds the pressurized lubricating fluid to the bearing to fill the bearing with lubricant or replenish lubricant that was lost.
A number of environments that until now could use the advantages of a non-contact seal have not been able to take advantage of the centrifugal pressure seals for various reasons. For example, the seal shown in the Ernst patent is situated immediately adjacent the bearing being serviced by the non-contact seal. Greater flexibility in use of the centrifugal pressure seal would be enjoyed if the seal did not have to be directly adjacent the bearing. The centrifugal seal could also enjoy wider use if the seal could service multiple bearings from a location remote from the bearing. Also the centrifugal seal until now has not been available for use with vertically oriented shafts because of the problem of the lubricating fluid draining from the seal. Solutions to these and other problems are provided by the present invention.